Re: [patch] gcov: cleanup an allocation in new_node()

From: Peter Oberparleiter
Date: Thu Sep 13 2012 - 08:43:05 EST

On 11.09.2012 13:13, Dan Carpenter wrote:
1) kcalloc(1, ...) can be replaced with kzalloc().
2) There was a small leak if the debugfs_create_dir() fails.
3) I removed a pr_warning("out of memory\n") because kmalloc() already
prints a more useful failure message in the unlikely case of an
allocation failure.

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

diff --git a/kernel/gcov/fs.c b/kernel/gcov/fs.c
index 9bd0934..132168f 100644
--- a/kernel/gcov/fs.c
+++ b/kernel/gcov/fs.c
@@ -437,7 +437,7 @@ static struct gcov_node *new_node(struct gcov_node *parent,
if (!node)
goto err_nomem;
if (info) {
- node->loaded_info = kcalloc(1, sizeof(struct gcov_info *),
+ node->loaded_info = kzalloc(sizeof(struct gcov_info *),

I'd like to keep using kcalloc here since node->loaded_info is an array.

if (!node->loaded_info)
goto err_nomem;
@@ -451,8 +451,7 @@ static struct gcov_node *new_node(struct gcov_node *parent,
node->dentry = debugfs_create_dir(node->name, parent->dentry);
if (!node->dentry) {
pr_warning("could not create file\n");
- kfree(node);
- return NULL;
+ goto err_info;

I agree that this is a potential memory leak - good find!

if (info)
add_links(node, parent->dentry);
@@ -461,9 +460,11 @@ static struct gcov_node *new_node(struct gcov_node *parent,

return node;

+ if (info)
+ kfree(node->loaded_info);

The 'if' here is not necessary: node->loaded_info is either zero (kfree tolerates NULL) or requires freeing. With the removal of the pr_warning below, the additional kfree can also be added to err_nomem (no need for another label) though then it should probably also be renamed.

- pr_warning("out of memory\n");
return NULL;

Peter Oberparleiter

Peter Oberparleiter
Linux on System z Development - IBM Germany

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at